Diamond



FIG. 1 is side elevational view of a diamond showing my new design;

FIG. 2 is a top plan view;

FIG. 3 is a bottom plan view;

FIG. 4 is a side elevational view of a diamond showing a second embodiment of my new design;

FIG. 5 is a top plan view of FIG. 4; and,

FIG. 6 is a bottom plan view of FIG. 4. 

The ornamental design for a diamond, as shown and described. 